Author Holly Lisle is a great source of advice for writers regardless of whether or not you like her writing or even the genres she writes in (mostly fantasy). Her website offers a great many FAQs on various fiction writing topics, and her email list regularly offers tips and suggestions that I have found useful. She also offers a number of books and courses on writing for people who are willing to pay for them. I haven't tried any of these yet.
But that's not why I'm here today. I'm here today because via her email list I found a free "mini-course" called Create a Professional Plot Outline. It's a short e-book in PDF form combined with a handful of email lessons to follow up.
I was skeptical at first, because I'm rarely much for plot outlines, but two email lessons in I must say I'm pretty impressed. It's not a system I'd recommend to someone who already knows the whole story they're writing; it's definitely written for someone who finds themselves getting bogged down in the plot or not sure where to start. (ie. me) I've never found a plotting system that worked for me before, but I'm making definite progress with this one that I've not had before.
I'll have to revisit the subject when I've finished the email course, but in the meantime, I see no reason not to recommend something I've found useful and has the added benefit of being free.
(Disclaimer: Holly Lisle offers an Affiliate Program for her books and courses. I am not a member of that program.)